package config

import (
	"fmt"
	"maps"
	"net/url"

	"github.com/ilyakaznacheev/cleanenv"
	log "github.com/sirupsen/logrus"
)

type AzureStorageConfig struct {
	AccountName string `env:"AZ_ACCOUNT_NAME"`
	Container   string `env:"AZ_CONTAINER"`
	AccountKey  string `env:"AZ_ACCOUNT_KEY"`
	UseHTTPS    bool   `env:"AZ_USE_HTTPS" env-default:"true"`
	ServiceURL  string `env:"AZ_SERVICE_URL"`
	Prefix      string `env:"AZ_PREFIX"`
	Enabled     bool   `env:"AZ_STORAGE_ENABLED"`
}

type appConfig struct {
	SourceDbUrl     string `env:"SOURCE_DB_URL"`
	SourceDbHost    string `env:"SOURCE_DB_HOST"`
	SourceDbPort    string `env:"SOURCE_DB_PORT"`
	SourceDbName    string `env:"SOURCE_DB_NAME"`
	SourceDbUser    string `env:"SOURCE_DB_USER"`
	SourceDbPwd     string `env:"SOURCE_DB_PWD"`
	SourceDbOptions string `env:"SOURCE_DB_OPTIONS"`
	TargetDbUrl     string `env:"TARGET_DB_URL"`
	TargetDbHost    string `env:"TARGET_DB_HOST"`
	TargetDbPort    string `env:"TARGET_DB_PORT"`
	TargetDbName    string `env:"TARGET_DB_NAME"`
	TargetDbUser    string `env:"TARGET_DB_USER"`
	TargetDbPwd     string `env:"TARGET_DB_PWD"`
	TargetDbOptions string `env:"TARGET_DB_OPTIONS"`
	LogLevel        string `env:"LOG_LEVEL" env-default:"INFO"`
	AzureStorage    AzureStorageConfig
}

func (c *appConfig) ResolveSourceDbUrl(dbType string) (string, error) {
	if c.SourceDbUrl != "" {
		return c.SourceDbUrl, nil
	}
	u, err := buildDbUrl(dbType, c.SourceDbHost, c.SourceDbPort, c.SourceDbName, c.SourceDbUser, c.SourceDbPwd, c.SourceDbOptions)
	if err != nil {
		return "", fmt.Errorf("source DB: %w", err)
	}
	return u, nil
}

func (c *appConfig) ResolveTargetDbUrl(dbType string) (string, error) {
	if c.TargetDbUrl != "" {
		return c.TargetDbUrl, nil
	}
	u, err := buildDbUrl(dbType, c.TargetDbHost, c.TargetDbPort, c.TargetDbName, c.TargetDbUser, c.TargetDbPwd, c.TargetDbOptions)
	if err != nil {
		return "", fmt.Errorf("target DB: %w", err)
	}
	return u, nil
}

func buildDbUrl(dbType, host, port, name, user, pwd, options string) (string, error) {
	if host == "" {
		return "", fmt.Errorf("DB_HOST is required when DB_URL is not set")
	}
	if name == "" {
		return "", fmt.Errorf("DB_NAME is required when DB_URL is not set")
	}
	if user == "" {
		return "", fmt.Errorf("DB_USER is required when DB_URL is not set")
	}

	switch dbType {
	case "sqlserver":
		if port == "" {
			port = "1433"
		}
		q := url.Values{}
		if options != "" {
			extra, err := url.ParseQuery(options)
			if err != nil {
				return "", fmt.Errorf("invalid DB_OPTIONS: %w", err)
			}
			maps.Copy(q, extra)
		}
		q.Set("database", name)
		u := &url.URL{
			Scheme:   "sqlserver",
			Host:     host + ":" + port,
			User:     url.UserPassword(user, pwd),
			RawQuery: q.Encode(),
		}
		return u.String(), nil

	case "postgres":
		if port == "" {
			port = "5432"
		}
		u := &url.URL{
			Scheme:   "postgres",
			Host:     host + ":" + port,
			User:     url.UserPassword(user, pwd),
			Path:     "/" + name,
			RawQuery: options,
		}
		return u.String(), nil

	default:
		return "", fmt.Errorf("unknown db type %q — cannot build URL from individual components", dbType)
	}
}

func getAppConfig() appConfig {
	var cfg appConfig

	err := cleanenv.ReadConfig(".env", &cfg)
	if err != nil {
		log.Warn("Could not load .env file")
	}

	err = cleanenv.ReadEnv(&cfg)
	if err != nil {
		log.Fatalf("Error al cargar variables: %v", err)
	}

	return cfg
}

var App appConfig = getAppConfig()